"The principle objective of mechanics of materials is to determine the stresses, strains, and displacements in structures and their components due to loads acting on them. If we can find these quantities for all values of the loads that cause failure, we will have a complete picture of the mechanical behavior of these structures. An understanding of the mechanical behavior is essential to the safe design of all types of structures, whether airplanes and antennas, buildings and bridges, machines and motors, or ships and spacecraft."

AXIAL FORCE
A FORCE APPLIED PARALLEL TO THE SYMMETRY AXIS OF AN OBJECT

CROSS SECTION
AN INTERIOR VIEW OF A CROSS-CUT THROUGH AN OBJECT

FORCE
A PUSH OR A PULL

FORCE

PRISMATIC
AN OBJECT HAVING A CONSTANT CROSS SECTIONAL AREA OVER ITS FULL LENGTH

PRISMATIC BAR
A BAR HAVING A CONSTANT CROSS SECTIONAL AREA OVER ITS FULL LENGTH

STRAIN

STRESS

STRESS

TENSILE STRESSES